The present invention is directed to pesticidal activity and more particularly, to the effect on octopamine receptors in cockroaches and other invertebrates by plant essential oils and their constituents.
The present invention relates to a method of controlling pests and more particularly to a method of preparing and applying a pesticide which affects octopamine receptor sites in invertebrates.
Many chemicals and mixtures have been studied for pesticidal activity for many years with a goal of obtaining a product which is selective for invertebrates such as insects, arachnids and larvae thereof and has little or no toxicity to vertebrates such as mammals, fish, fowl and other species and does not otherwise persist in, and damage, the environment. Most products of which the applicants are aware and which have sufficient pesticidal activity to be of commercial significance, also have toxic or deleterious effects on mammals, fish, fowl or other species which are not the target of the product. For example, organophosphorus compounds and carbamates inhibit the activity of acetylcholinesterase in insects as well as in all classes of animals.
Several studies disclose the use of naturally occurring substances as insecticides but the references are mostly for a single species of insect or for a natural product which has many components. Thus, U.S. Pat. No. 5,118,506 to Eichofer discloses pine oil for use against fire ants. The pine oil is disclosed to be composed of thirty-eight (38) components and alpha-pinene is considered to be as effective as the unrefined pine oil. In U.S. Pat. No. 4,933,371, Hink et al control fleas and ticks with linalool, D-limonene and α-terpineol. Mixtures of these ingredients were not disclosed. Rod, in U.S. Pat. No. 5,653,991 discloses several monoterpenes which have insecticidal activity. Japanese Patent Abstract JP 05 039 203A discloses miticidal compositions having no residual toxicity. Patent Abstract of Japan JP 04 059 703, Application No. 02166735discloses a miticide. Coats et al in ACS Symposium Series 1991, pages 305-316 disclose insecticidal activity of several monoterpenoids. None of these references suggest a mode of action. Also, the references generally show that an active ingredient is useful against a narrow range of species of pests and do not have a broad spectrum of activity against many species of pests. These references do not disclose a preselected mixture of several active ingredients to provide an insecticide. The present applicants also have disclosed naturally occurring materials which have pesticidal activity in U.S. Pat. Nos. 6,004,569 and 6,183,767. Chlordimeform and related formamidines are known to act on octopamine receptors of insects but have been removed from the market because of cardiotoxic potential in vertebrates and carcinogenicity in animals and a varied effect on different insects. Also, very high doses are required to be toxic for certain insect species.
It is postulated that amidine compounds affect the octopamine sensitive adenylate cyclase present in insects [Nathanson et al, Mol. Pharmacol 20:68-75 (1981) and Nathanson, Mol. Pharmacol 28:254-268 (1985)]. Another study was conducted on octopamine uptake and metabolism in the insect nervous system [Wierenga et al, J Neurochem 54, 479-489 (1990)]. These studies were directed at nitrogen containing compounds which mimic the octopamine structure and do not include compounds consisting of only carbon, hydrogen and oxygen.
Insecticides such as trioxabicyclooctanes, dithianes, silatranes, lindane, toxaphen, cyclodienes and picrotoxin act on the GABA (gamma amino butyric acid) receptor. However, these products also affect mammals, birds, fish and other species.
There is a need for a broad spectrum pesticide which targets and controls only invertebrates and does not produce unwanted and harmful affects on other species, and a method for using this pesticide.